Drawbacks of Simple Implementation
Explore the problems with simple polymorphic component implementation.
We'll cover the following
We now have something of a standard polymorphic implementation. However, our implementation has a few problems. One of those problems is that the polymorphic prop can receive invalid HTML elements.
For example, it's currently possible for a user to go ahead and write something like the following:
<PolymorphicText as="educative">Hello Wrong Element</PolymorphicText>
Passing a wrong as attribute
The as prop passed here is educative.
The educative prop is obviously an incorrect HTML element, but the browser still tries to render it.
Inspecting the rendered element
Click the "Run" button and inspect the element rendered in the playground widget below.
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We should see an educative element rendered to the DOM.
This is far from ideal.
An optimal development experience should show some kind of error during development, in this case, to prevent the user from passing an invalid HTML element in the as prop. For example, a user may make a simple typo—divv instead of div—and they will get no indication of what’s wrong during development.
Incorrect attributes for valid elements
Let's consider the following component usage, which has incorrect attributes passed to the polymorphic component. In this example, an href attribute is passed to a span element.
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A consumer can pass a span element to the as prop and the href prop. This is technically invalid. A span element does not (and should not) take in an href attribute. That is an invalid HTML syntax.
However, as it stands, a consumer of the component we've built could go ahead and write this, and they wouldn't get any errors during development.